Mass-gathering decision making and its implementation during the COVID-19 pandemic
Authors: Amaia Artazcoz Glaria, Lucia Mullen, Amanda Kobokovich, Albis Francesco Gabrielli, Rebecca Grant, Nedret Emiroglu, Ninglan Wang
Journal: The Lancet Public Health (2023)

Mass-gathering events are a public health challenge and have the potential to amplify the transmission of infectious diseases.1Memish ZA Steffen R White P et al.Mass gatherings medicine: public health issues arising from mass gathering religious and sporting events.Lancet. 2019; 393: 2073-2084Summary Full Text Full Text PDF PubMed Scopus (165) Google Scholar During the COVID-19 pandemic, WHO and the Johns Hopkins Center for Health Security (Johns Hopkins University, Baltimore, MD, USA)—a WHO Collaborating Centre for Global Health Security—developed a global database of mass gatherings, which we continue to maintain. The purpose of this database is to monitor the planning and execution of mass-gathering events and to document the uptake of WHO-recommended policies by organisers;2WHOPublic health for mass gatherings: key considerations.https://apps.who.int/iris/handle/10665/162109Date: 2015Date accessed: September 5, 2023Google Scholar, 3WHOKey planning recommendations for mass gatherings in the context of COVID-19: interim guidance, first issued 14 February 2020, third update 4 November 2021.https://apps.who.int/iris/handle/10665/348018Date: 2021Date accessed: September 5, 2023Google Scholar, 4WHOMass gathering COVID-19 risk assessment tool: generic events, version 3, 16 June 2022.https://apps.who.int/iris/handle/10665/356509Date: 2022Date accessed: September 5, 2023Google Scholar for example, the use of a risk-based approach. Events in the database are identified via Google search and include sporting, political, business, health-campaign, entertainment, cultural, and religious events. Upcoming gatherings are also identified by liaising with event organisers and health authorities; WHO regional offices provide lists of upcoming gatherings for event-based epidemiological surveillance. From Jan 1, 2020, to July 31, 2023, the global database of mass gatherings collated information on 5737 events (figure). In early 2020, decisions to cancel or postpone events were often made hastily and typically viewed as reactive responses to uncertainty in the epidemiological situation. However, throughout 2020 and 2021, the number of event organisers who reported cancelling or postponing events on the basis of a risk assessment increased. In 2021, as increasing proportions of the global population were protected from severe COVID-19 through vaccination or previous infection and there was widespread awareness, use, and acceptance of public health and social measures (eg, physical distancing, improving ventilation, and use of masks) and a wide availability of SARS-CoV-2 diagnostic tests—including rapid antigen tests—decision making and implementation changed to event modification, rather than cancellation or postponement. From mid-2022 onwards, after the decreasing public health effects of SARS-CoV-2 transmission and the subsequent easing of many COVID-19-specific public health and social measures across most countries, many events proceeded without COVID-19-specific modifications. The global database of mass gatherings was used by WHO to support efforts to identify countries or settings with increasing incident COVID-19 cases and to prepare for events by applying a risk-based approach, so that events could be as safe as possible. This risk-based approach included proactive engagement by WHO with health authorities and event organisers to encourage implementing additional measures to prevent and mitigate any increased risk of SARS-CoV-2 transmission. The scope of the database has since been expanded to include other disease outbreaks, including mpox (formerly known as monkeypox). Collating information about mass-gathering decision making and implementation has identified a pattern throughout the COVID-19 pandemic, from predominant cancellations and postponements of gatherings to events proceeding without specific risk-mitigation measures. This pattern followed the evolution of the broad public health response to the COVID-19 pandemic. The global database of mass gatherings emphasises the need for systematic use and documentation of a risk-based approach for decision making and identifies trends that can inform such decision making by WHO, event organisers, and public health authorities during future public health emergencies. This online publication has been corrected. The corrected version first appeared at thelancet.com/public-health on January 2, 2024 This online publication has been corrected. The corrected version first appeared at thelancet.com/public-health on January 2, 2024 RG receives consulting fees from WHO. All other authors declare no competing interests. We thank the event organisers and health authorities for engaging with WHO on mass-gathering decision making and implementation. We thank members of the WHO Incident Management Teams for COVID-19 in WHO headquarters and regional offices. We are particularly grateful to the mass-gatherings teams in WHO regional offices for their contributions to the identification and monitoring of mass-gathering events. We also thank the members of the COVID-19 Epidemiology Pillar at WHO headquarters (Geneva, Switzeralnd) for their contributions to the figure and Maria Van Kerkhove (WHO, Geneva, Switzerland). We are grateful to Vanessa Grégoire, Clint Haines, Noelle Huhn, Crystal Watson, Murhaf Alkaddour, Camille Clausse-Pujo, Lauren Formica, Stephanie Marie Kenyon, Oyinkansola Oladapo, and Zeba Nauroz (Johns Hopkins Center for Health Security, Johns Hopkins University, Baltimore, MD, USA) for their contributions to database development and management. Correction to Lancet Public Health 2023; 8: e912–13Glaria AA, Mullen L, Kobokovich A, et al. Mass-gathering decision making and its implementation during the COVID-19 pandemic. Lancet Public Health 2023; 8: e912–13—In this Correspondence, the spelling of author Amanda Kobokovich's name was incorrect. This correction has been made as of Jan 2, 2024. Full-Text PDF Open Access